A wavefront correction deformable mirror device

Abstract

The present invention relates to the field of deformable mirror technology, specifically a wavefront correction deformable mirror device, comprising a mirror body and a main mirror chamber, a connecting assembly being provided between the mirror body and the main mirror chamber, and a plurality of actuator assemblies being installed on the main mirror chamber. The connecting assembly comprises a support member and a protective member installed on the main mirror chamber, and the actuator assembly comprises an adhesive head, an off-axis correction joint, a driver, an axial preload member, and a pressing member that are sequentially arranged and connected together. The present invention adopts a support member in conjunction with an off-axis correction joint, effectively improving the adaptability of the present invention in different temperature environments and reducing the difficulty of assembly, thereby improving the convenience and efficiency of assembly and maintenance. At the same time, a preload force is increased between the actuator assembly and the mirror body, thereby improving the speed and accuracy of the actuator response, and effectively improving the stability and reliability of the optical system as a whole. Moreover, the preload force between the actuator assembly and the mirror body can be adjusted after the pressing member presses the axial preload member.

Description

Technical Field

[0001] The present invention relates to the technical field of deformable mirrors, and in particular to a wavefront correction deformable mirror device. Background Art

[0002] With the widespread application of modern optical systems in high-precision imaging and optical measurement, particularly in deep ultraviolet (DUV) optical imaging, wavefront correction has become a key technology for ensuring system performance. Wavefront distortion, caused by various errors or imperfections in the optical system, can severely impact image quality. In the DUV optical band, the imaging quality requirements for objectives are extremely high, and wavefront errors are particularly sensitive. Even minor aberrations can cause image blur or distortion. Therefore, wavefront correction for DUV objectives has become a significant technical challenge.

[0003] Wavefront correction is mainly achieved by driving the mirror deformation through the displacement of the actuator. The correction accuracy and correction speed of the existing wavefront correction deformable mirror device need to be further improved. Its correction accuracy and correction speed are easily affected by changes in ambient temperature and installation errors. Due to the difference in thermal expansion coefficient of the material, the deformation of the deformable mirror will be significantly affected by temperature fluctuations, resulting in unstable wavefront correction of the deformable mirror under different working environments, which will in turn reduce its correction accuracy; secondly, the number of actuators is large and the installation space is limited, the installation accuracy requirements are high, and the installation and adjustment are difficult, so the existing wavefront correction deformable mirror device is prone to installation errors and reduces the correction accuracy and speed, thereby reducing the stability and reliability of the optical system. Summary of the Invention

[0004] The present invention provides a wavefront correction deformable mirror device to solve the problem in the related art that the wavefront correction deformable mirror device is easily affected by changes in ambient temperature and installation errors, resulting in reduced correction accuracy and speed, which in turn affects the stability and reliability of the optical system.

[0005] The present invention provides a wavefront correction deformable mirror device, which includes a mirror body and a main mirror chamber, a connecting assembly is provided between the mirror body and the main mirror chamber, a plurality of actuator assemblies are installed on the main mirror chamber, the mirror body is installed on one side of the main mirror chamber through the connecting assembly, the actuator assembly is installed into the main mirror chamber from the other side and connected to the mirror body, and the plurality of actuator assemblies are evenly distributed in an array, the connecting assembly includes a support member and a protective member installed on the main mirror chamber, the support member is connected to the side of the mirror body and is a single-degree-of-freedom flexible hinge structure, and is used to automatically compensate for the mirror body and the support member due to Deformation difference caused by temperature change; the protective part limits the mirror body from the end face, and the actuator assembly includes a sticky head, an off-axis correction joint, a driver, an axial preload and a pressing member that are arranged and connected together in sequence. The sticky head is connected to the mirror body, and the main mirror chamber limits the sticky head in the radial direction to form a first limiting area. The pressing member is threadedly connected to the main mirror chamber and presses the axial preload, forming a preload force between the actuator assembly and the mirror body, and the axial preload is threadedly connected to the driver. After the pressing member is tightened, the preload force between the actuator assembly and the mirror body is adjusted by rotating the axial preload.

[0006] In a possible implementation, a direction of the threaded connection between the axial preload member and the driver is opposite to a direction of the threaded connection between the pressing member and the primary mirror chamber.

[0007] In one possible implementation, the axial preload member is provided with an inner hexagonal adjustment area, and the pressing member is provided with a through slot. An external inner hexagonal wrench passes through the through slot and cooperates with the inner hexagonal adjustment area to control the rotation of the axial preload member.

[0008] In one possible implementation, an annular groove is provided on the axial preload member, and the pressing member includes a connecting seat provided with an annular platform. The annular platform cooperates with the annular groove to limit the axial preload member in the radial direction, and the annular platform is threadedly connected to the main mirror chamber.

[0009] In one possible implementation, the plurality of actuator assemblies are distributed in a hexagonal, axisymmetric manner.

[0010] In a possible implementation, there are a plurality of support members and a plurality of protective members, both of which are evenly distributed along the circumference of the mirror body, and the support members and the protective members are alternately distributed in sequence.

[0011] In one possible implementation, a plurality of protrusions are provided on the mirror body, the protrusions corresponding to the actuator components one by one, and the adhesive head is provided with grooves that cooperate with the protrusions.

[0012] The above one or more technical solutions in the embodiments of the present invention have at least one of the following technical effects: 1. The present invention adopts a support member in combination with an off-axis correction flexible joint, which effectively improves the adaptability of the present invention in different temperature environments and reduces the difficulty of assembly, thereby improving the convenience and efficiency of assembly and maintenance. At the same time, the preload force is increased between the actuator assembly and the mirror body, thereby improving the speed and accuracy of the actuator response, and effectively improving the stability and reliability of the optical system as a whole. The preload force between the actuator assembly and the mirror body can be adjusted after the clamping member clamps the axial preload member, thereby effectively improving the convenience of maintenance, disassembly, and installation adjustment of the present invention, thereby ensuring the long-term stability and reliability of the optical system.

[0013] 2. In the present invention, the direction of the threaded connection between the axial preload and the driver is opposite to the direction of the threaded connection between the clamping member and the primary mirror chamber, and an inner hexagonal adjustment area is provided on the axial preload. The rotation of the axial preload can be controlled by cooperating with the inner hexagonal adjustment area through the inner hexagonal wrench, which further improves the convenience of maintenance and installation adjustment. In the process of increasing the preload force, the clamping member and the primary mirror chamber will not loosen, thereby ensuring the stability of the connection. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a structural schematic diagram of a mirror body and a main mirror chamber of a wavefront correction deformable mirror device provided by an embodiment of the present invention.

[0015] Figure 2 It is a schematic diagram of the partial structure of a wavefront correction deformable mirror device provided by an embodiment of the present invention.

[0016] Figure 3 It is a schematic cross-sectional structural diagram of a wavefront correction deformable mirror device provided by an embodiment of the present invention.

[0017] Figure 4 yes Figure 3 Enlarged view of point A in the middle.

[0018] Figure 5 Schematic diagram of the structure of an actuator assembly of a wavefront correction deformable mirror device provided by an embodiment of the present invention.

[0019] Figure 6 It is a structural schematic diagram of a support member of a wavefront correction deformable mirror device provided by an embodiment of the present invention.

[0020] In the figure: 1. Mirror body; 2. Main mirror chamber; 3. Connecting assembly; 31. Support member; 32. Protective member; 4. Actuator assembly; 41. Adhesive head; 42. Off-axis correction flexible joint; 43. Driver; 44. Axial preload member; 45. Pressing member; 451. Annular table; 452. Connecting seat; 46. Hexagonal adjustment area; 47. Through groove; 48. Annular groove; 49. Groove; 5. Bump. DETAILED DESCRIPTION

[0021] To make the above-mentioned objects, features, and advantages of the present invention more readily apparent, specific embodiments of the present invention are described in detail below with reference to the accompanying drawings. The following description sets forth numerous specific details to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways than those described below, and those skilled in the art may make similar modifications without departing from the scope of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0022] See also Figure 1 、 Figure 2 、 Figure 3 and Figure 5 A wavefront correction deformable mirror device includes a mirror body 1 and a main mirror chamber 2. A connecting component 3 is provided between the mirror body 1 and the main mirror chamber 2. A plurality of actuator components 4 are installed on the main mirror chamber 2. The mirror body 1 is installed on the front side of the main mirror chamber 2 through the connecting component 3. The actuator component 4 is installed into the main mirror chamber 2 from the rear side and connected to the mirror body 1. The actuator component 4 is also disassembled and replaced from the rear side. The plurality of actuator components 4 are distributed in a hexagonal axisymmetric manner (such as Figure 2 As shown), there are a total of nineteen independent actuator components 4. The actuator components 4 are responsible for adjusting the shape of the mirror body 1 in real time, accurately correcting the wavefront error, improving the imaging accuracy of the deep ultraviolet objective lens, and ensuring the quality of imaging.

[0023] See Figure 1 、 Figure 3 and Figure 6 The connecting assembly 3 includes a support member 31 and a protective member 32 mounted on the main mirror chamber 2. The support member 31 and the protective member 32 are detachably fixed to the main mirror chamber 2 by threaded fasteners. The number of support members 31 is several and evenly distributed along the circumference of the mirror body 1, such as Figure 1 As shown, there are three support members 31 and they are connected to the side of the mirror body 1 by bonding, providing support force for the mirror body 1 from the side to ensure the stability of the position accuracy of the mirror body 1, and the support member 31 is a single-degree-of-freedom flexible hinge structure. When the ambient temperature changes to cause different deformation amounts of the mirror body 1 and the support member 31, the support member 31 with a single-degree-of-freedom flexible hinge structure will automatically provide appropriate flexible compensation to reduce the wavefront error caused by the inconsistent deformation of the mirror body 1 and the support member 31, thereby improving the stability of the correction performance of the present invention at different temperatures.

[0024] See Figure 1 and Figure 3 The number of the protective members 32 is several and the protective members 32 limit the mirror body 1 from the edge of the front end surface of the mirror body 1, such as Figure 1As shown, there are three protective members 32 and they are evenly distributed along the circumference of the mirror body 1. The protective members 32 and the support members 31 are alternately distributed in sequence, which improves the uniformity of the force applied to the mirror body 1 and further helps to improve the stability of the position accuracy of the mirror body 1.

[0025] See Figure 1 、 Figure 2 、 Figure 3 、 Figure 4 and Figure 5 The actuator assembly 4 includes a sticky head 41, an off-axis correction flexible joint 42, a driver 43, an axial preload 44, and a pressing member 45, which are sequentially arranged and connected from front to back. The sticky head 41 is connected to the mirror body 1 by means of adhesion, and the main mirror chamber 2 limits the sticky head 41 in the radial direction; Figure 3 As shown, the primary mirror chamber 2 is provided with a plurality of cylindrical mounting cavities for mounting the actuator assembly 4. The adhesive head 41 is a circular seat with a truncated cone on the front side. The peripheral side of the circular seat is in contact with the inner side of the mounting cavity, thereby limiting the adhesive head 41 to a certain extent without affecting the axial movement of the actuator assembly 4. The off-axis correction flexible joint 42 is connected to the adhesive head 41 by fastening with threaded fasteners and connected to the driver 43 by bonding. The off-axis correction flexible joint 42 is an existing X-Flexure flexible joint, as shown in FIG. Figure 5 As shown, the circular cutout on the off-axis correction flexible joint 42 releases the rotational freedom in two directions perpendicular to the axial direction, which can effectively absorb and compensate for small misalignment errors that occur during the installation process, and correspondingly reduces the requirements for the installation accuracy of the actuator assembly 4, wherein the driver 43 can be a piezoelectric ceramic motor.

[0026] See Figure 3 、 Figure 4 and Figure 5 The clamping member 45 is threadedly connected to the main mirror chamber 2 and presses the axial pre-tightening member 44. Combined with the protective member 32 limiting the mirror body 1 from the front end, a stable pre-tightening force is formed between the actuator assembly 4 and the mirror body 1, thereby improving the response speed and accuracy of the actuator assembly 4, thereby improving the correction speed and accuracy of the present invention, and the axial pre-tightening member 44 is threadedly connected to the driver 43. After the clamping member 45 presses the axial pre-tightening member 44, the axial pre-tightening member 44 can be rotated to adjust the distance between the clamping member 45 and the driver 43, thereby adjusting the pre-tightening force between the actuator assembly 4 and the mirror body 1, thereby correspondingly improving the installation and maintenance efficiency and convenience of the deformable mirror device. Among them, the direction of the threaded connection between the axial pre-tightening member 44 and the driver 43 is opposite to the direction of the threaded connection between the clamping member 45 and the main mirror chamber 2. In the process of rotating the axial pre-tightening member 44 to increase the pre-tightening force, the clamping member 45 and the main mirror chamber 2 will not loosen, thereby ensuring the stability of their connection.

[0027] See Figure 3and Figure 4 The axial preload member 44 is provided with an inner hexagonal adjustment area 46, and the pressing member 45 is provided with a through slot 47. An external inner hexagonal wrench passes through the through slot 47 and cooperates with the inner hexagonal adjustment area 46 to control the rotation of the axial preload member 44, so as to facilitate the adjustment of the preload force after the deformable mirror device is assembled.

[0028] See Figure 3 and Figure 4 An annular groove 48 is provided on the axial preload member 44, and the pressing member 45 includes a connecting seat 452 provided with an annular platform 451. The annular platform 451 is threadedly connected to the primary mirror chamber 2, and the annular platform 451 cooperates with the annular groove 48 to limit the axial preload member 44 in the radial direction, thereby further improving the assembly accuracy.

[0029] See Figure 2 、 Figure 3 and Figure 5 The mirror body 1 is provided with a number of cylindrical protrusions 5, which correspond one-to-one to the actuator components 4. The adhesive head 41 is provided with grooves 49 that cooperate with the protrusions 5. The protrusions 5 are inserted into the grooves 49 to connect the adhesive head 41 and the mirror body 1 together. On the one hand, it facilitates the connection and installation, and on the other hand, it is beneficial to improve the connection accuracy and stability after connection.

[0030] In the embodiments of the present invention, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Furthermore, a first feature being "above," "above," or "above" a second feature may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. A first feature being "below," "below," or "below" a second feature may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0031] In the description of the present invention, it should also be noted that, unless otherwise expressly specified or limited, the terms "disposed," "connected," "installed," and "connected" should be understood in a broad sense. For example, they may refer to fixed or detachable connections, integral or sliding connections; mechanical or electrical connections; direct or indirect connections through an intermediate medium; or internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0032] The embodiments of this specific implementation method are all preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Therefore, any equivalent changes made based on the structure, shape, and principle of the present invention should be included in the scope of protection of the present invention.

Claims

1. A wavefront correction deformable mirror device, comprising a mirror body and a primary mirror chamber, characterized in that: A connecting assembly is provided between the mirror body and the main mirror chamber. A plurality of actuator assemblies are installed on the main mirror chamber. The mirror body is installed on one side of the main mirror chamber through the connecting assembly. The actuator assembly is installed into the main mirror chamber from the other side and connected to the mirror body. The plurality of actuator assemblies are evenly distributed in an array. The connection assembly includes a support member and a protective member installed on the main mirror chamber. The support member is connected to the side of the mirror body and has a single-degree-of-freedom flexible hinge structure. It is used to automatically compensate for the deformation difference between the mirror body and the support member due to temperature changes. The protective member limits the mirror body from the end face. The actuator assembly includes a sticking head, an off-axis correction flexible joint, a driver, an axial pre-tightening member, and a pressing member, which are sequentially arranged and connected together. The sticking head is connected to the mirror body. The pressing member is threadedly connected to the main mirror chamber and presses the axial pre-tightening member to form a pre-tightening force between the actuator assembly and the mirror body. The axial pre-tightening member is threadedly connected to the driver. After the pressing member is pressed, the pre-tightening force between the actuator assembly and the mirror body is adjusted by rotating the axial pre-tightening member. The threaded connection direction between the axial pre-tightening member and the driver is opposite to the threaded connection direction between the pressing member and the primary mirror chamber.

2. The wavefront correction deformable mirror device according to claim 1, characterized in that: The axial preload member is provided with an inner hexagonal adjustment area, and the pressing member is provided with a through slot. An external inner hexagonal wrench passes through the through slot and cooperates with the inner hexagonal adjustment area to control the rotation of the axial preload member.

3. The wavefront correction deformable mirror device according to claim 1, characterized in that: An annular groove is provided on the axial preload member, and the pressing member includes a connecting seat provided with an annular platform. The annular platform cooperates with the annular groove to limit the axial preload member in the radial direction, and the annular platform is threadedly connected to the main mirror chamber.

4. The wavefront correction deformable mirror device according to claim 1, characterized in that: The actuator assemblies are distributed in a hexagonal axisymmetric manner.

5. The wavefront correction deformable mirror device according to claim 1, characterized in that: There are a plurality of support members and protective members, both of which are evenly distributed along the circumference of the mirror body, and the support members and protective members are alternately distributed in sequence.

6. The wavefront correction deformable mirror device according to claim 1, characterized in that: The mirror body is provided with a plurality of protrusions, which correspond to the actuator components one by one, and the adhesive head is provided with grooves that match the protrusions.

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